Improvement for knitted fabric linking machine

ABSTRACT

An improved work cylinder support arrangement for a circular knitted garment linking machine permits the cylinder to be automatically indexed, pivoted away from the needles of the machine upon completion of a sewing operation, and quickly removed and exchanged for another cylinder containing other knitted garment sections to be seamed.

UNITED STATES PATENTS Darandik 112/25 0 1 v United States Patent 11 1 [1.11 3,802,358 Anfruns Apr. 9, 1974 [54] IMPROVEMENT FOR KNITTED FABRIC 3,292,563 12/1966 Matthews ll2/25 LINKING MACHINE 2,264,234 ll/l94l Bell ll2/25 1.966377 7/1934 De Spain 112/25 Inventor Luis Semis Anfruns, Panama -12 1,026,808 5/1912 Koehler 112 25 and 4, Barcelona, Spain [22] Filed: JuneZ, 1972. Primary Examiner-Geo. V. Larkin [21] App], No: 259 265 Attorney, Agent, or FirmBacon & Thomas (30] Foreign Application Priority Data [57] ABSTRACT June 8, 1971 Spain 392466 An improved work cylinder pp arrangement for a circular knitted garment linking machine permits the (SI. cylinder to be automatically indexed, pivoted away [58] i 1 l2/25 27 from the needles of the machine upon completion of a sewing operation, and quickly removed and ex- II 56] References Cited changed for another cylinder containing other knitted garment sections to be seamed.

8 Claims, 5 Drawing Figures PATENFEMPR 9 I974 SHEET l B? 2 IMPROVEMENT FOR KNITTED FABRIC LINKING MACHINE This invention relates to an improvement in sewing machines or loopers for joining segments or sections of knitted garments, and specifically to an improved work holding cylinder and a supporting and indexing arrangement for the work cylinder. Prior art machines of this type are shown in US. Pat. Nos. 1,026,808, 1,966,337, and 2,862,464.

It is known that in machines of this type, two coaxial discs of relatively large diameter having radially extending points thereon for holding the loops of the circular knitted garment sections to be joined are conventionally used. These discs are not relatively separable during the various phases of operation of the machine. Moreover, these discs, being of large diameter, tend to distort and stress the circular garment sections strung on the points of the discs, since the knitted garment material passes over the outer diameter of the discs, not through the centers thereof. This tension is particularly significant in the sewing of circular garments such as the toe part of stockings having cavities for the individual toes, and results .in a less than desirable seam between the sections being joined.

In addition, since the discs cannot be separated during the various phases of the work loading and sewing operations, the machine must be still while the loops of the garment are strung on the points of the discs, resulting in obvious inefficiencies.

The present invention obviates these difficulties, and embodies a hollow cylindrical work holder having an axially extending set of points for engaging the fabric loops to be joined together. The cylinder is mounted in a sleeve assembly having an inner concentric bearing member that rotatably supports the work cylinder through a friction fit arrangement. The sleeve assembly further includes pawl means for engaging ratchet teeth on the cylinder to rotate the latter in a step-by-step manner, means for obtaining the quick release of the cylinder from the sleeve, and means for enabling the sleeve and cylinder to be automatically pivoted away from the machine needles upon the completion of each joining cycle.

The cylinderv permits the two garment sections being joined together to extend axially through the center of the annular opening through the cylinder, with the loops of both sections strung over a single set of points on the cylinder.

The invention therefore makes for more efficient production since multiple cylinders can be preloaded with garment sections to be joined and replaced quickly in the machine after each looping or sewing cycle, and produces a better seam since the tensions therwise introduced to the garment sections with the prior art discs are no longer present.

With further reference to the accompanying drawings which illustrate by way of example a preferred embodiment of the present invention:

FIG. 1 is an elevational side view of the work cylinder and sleeve assembly of this invention in position for a sewing operation;

FIG. 2 is an end elevation view of the work cylinder and sleeve assembly, showing the pawl and ratchet arrangement;

FIG. 3 is a partial sectional view of the work cylinder with the garment sections to be joined thereon;

FIG. 4 is a view similar to FIG. 1, with the sleeve and cylinder pivoted; and I FIG. 5 is a partial sectional view of the work cylinder and sleeve showing the cylinder being released from the sleeve after the sewing'operation.

With specific reference to FIGS. 1 and 3, the work cylinder 1 of this invention is provided at its front end 2 with points 6 for receiving the individual loops of the sections 3, 4 of a circular knitted garment, such as a stocking having toe pieces 5. The cylinder is provided with ratchet teeth 11 the purpose of which will be explained below, and a tapered body portion la which decreases slightly in diameter towards the points 6.

The work cylinder 1 fits snugly within a cylinder supporting sleeve assembly 7 which, as shown in FIG. 5 includes an inner, concentric cylinder engaging sleeve member 8b rotatably supported with respect to the outer sleeve member 8a by means of roller bearings 8f or the equivalent. The inner sleeve member 812 includes an inner surface 8g tapered to conform with the outer peripheral surface la of cylinder 1 whereby firm insertion of cylinder 1 into sleeve assembly 7 results in a close friction fit between the cylinder and inner sleeve member 8b, with the cylinder 1 then being rotatably supported by means of bearing member 8b with respect to outer sleeve member 8a.

The sleeve assembly 7 further includes a rotatable work cylinder indexing ring 70 which carries a work cylinder driving pawl 9 (FIG. '2). A work cylinder noback pawl 10 is carried by outer sleeve member 8a, and a spring 10a connects the pawls for biasing them into engagement withthe ratchet teeth 11 of cylinder 1 when the cylinder and sleeve are assembled as shown in FIG. 1, for example.

Rotatably mounted on the sleeve assembly 7 is a quick release means for separating cylinder 1 from sleeve member 8 at the end of a sewing cycle, the quick release means including a threaded ring 8c received in ring 7a and having a handle 8d attached thereto for enabling an operator to back the ring 80 our of ring 7 to force the cylinder 1 out of engagement with inner sleeve member 8b by reason of the mutual engagement of the ring 8: and cylinder 1 in the area indicated at 80 when ring is backed out of ring 7a.

The sleeve assembly 7 is mounted for pivotal movement on member 14 of sewing machine 20 (FIG. 2) whereby pivotal movement of the sleeve assembly positioning rod or lever arm 14b about axis 14a causes corresponding pivotal movement of sleeve assembly 7 and cylinder 1 about the same axis, as shown in FIG. 4. For positioning the sleeve assembly 7 in proper synchronism with the sewing operation, a cam disc 13 having a female cam groove 15 and serrations 13a on its periphery is connected to rotate synchronously with the shaft 12 connected to the sewing machine needles (not shown) which extend into the upper area of points 6 when the machine is in the FIG. 1 operating mode. The cam groove 15 receives a cam follower on the opposite end of lever 14b from axis 14a in a conventional manner whereby rotation of cam disc 13 during the sewing operation causes the lever 14b to pivot between the positions illustrated in FIGS. 1 and 4. A tripper or tab 23 on cam disc 13 engages microswitch 22 each revolution of the disc to stop the operation of the needles while the cylinder 1 and sleeve assembly 7 are pivoted in the position of FIG. 4.

For stepwise rotation or indexing of the cylinder 1 during the sewing operation, push rod 16, actuated by cam follower 16a riding over serrations 13a on disc 13, reciprocates as indicated by the arrows in FIG. 1, resulting in crank arm 18 rocking about the pivotal at tachment to the machine element 19 and causing reciprocation of push rod 16b which in turn causes oscillation of ring 7a in the directions shown by arrows 7b (FIG. 2). The oscillation of ring 70 causes pawl 9 to drive work cylinder 1 clockwise through ratchet teeth 11 as viewed in FIG. 2, while pawl 10, held fixed on outer sleeve member 8a, prevents the cylinder from rotating counterclockwise during the return stroke of pawl 9. As seen in FIG. 4, the rod 16b is hinged centrally of its length to permit pivotal movement of sleeve assembly 7 without mechanical interference in the cylinder indexing linkage. As the cylinder 1 steps around, of course, the sewing machine needles perform the stitching operation on the loops of the knitted garment sections to be joined in the area of points 6.

Various details of the described embodiment could be varied, of course, to suit particular operational requirements. The cam form, push rod assembly, the sleeve support arrangement and other details could be modified within the scope of the present invention, which invention is intended to be encompassed only by the claims as follows:

I claim:

1. In a linking machine for joining together circular knitted garment sections, the improvement comprising an annular work cylinder having a single, axially extending annular row of points thereon for engaging the loops of a pair of circular knitted garment sections to be joined together by sewing, the said work cylinder supporting at least portions of each of the garment sections to be joined substantially concentrically therein during the linking operation.

2. In a linking machine including sewing needles for stitching together the loops of circular knitted garment sections to be joined, the improvement comprising an annular work cylinder having points for engaging the loops of the garment sections to be joined; the said work cylinder supporting at least portions of each of the garment sections to be joined substantially concentrically therewithin during the stitching operation, a pivotally mounted support means for mounting said work cylinder on said machine for both rotational motion about its longitudinal axis and pivotal movement about its transverse axis; and actuating means whereby said work cylinder can be pivoted about its transverse axis from a position where the points lie in proximity to the stitching area of the machine to a position where the points are inclined away from the stitching area.

3. The linking machine of claim 2 wherein said work cylinder support means further comprises a sleeve assembly for coaxially receiving and supporting said work cylinder within said assembly, said sleeve assembly comprising an outer sleeve member and a work cylinder engaging annular inner sleeve member, said inner sleeve member extending coaxially of said outer sleeve member and being pivotally supported for rotary motion about its longitudinal axis with respect to said outer sleeve member, said work cylinder extending axially through said inner sleeve member, said inner sleeve member further including means for engaging said work cylinder whereby the said work cylinder is supported for rotary motion with respect to said outer sleeve member, said outer sleeve member normally being held fixed against rotary motion on said linking machine.

4. The linking machine of claim 3 wherein the said work cylinder includes a conical tapered outer peripheral area, the tapered periphery converging towards the points of the work cylinder, and said inner sleeve means for engaging said work cylinder includes an inner tapered surface corresponding to the tapered periphery of the work cylinder, the inner sleeve member receiving and engaging the work cylinder through an interference friction fit.

5. The linking machine of claim 4 wherein said work cylinder includes an annular row of ratchet teeth, and said sleeve assembly further includes a work cylinder driving ring and a pawl connected thereto, said pawl engaging said ratchet teeth for causing intermittent, unidirectional rotary motion of said work cylinder when said pawl is driven in an oscillating manner through said driving ring, and means operating synchronously with the linking machine needles for actuating said driving ring in an oscillating manner.

6. The linking machine of claim 4 wherein said sleeve assembly further includes a work cylinder quick release means for enabling the work cylinder to be positively driven axially out of engagement with said inner sleeve member.

7. The linking machine of claim 2 wherein said actuating means for said work cylinder support means comprises a lever arm driven by a cam and follower means, the cam and follower means being driven synchronously with the linking machine needles whereby said lever arm is driven to cause said pivotal movement of said support means away from the needles once per linking cycle after each garment is completely joined.

8. The linking machine of claim 7 further including a microswitch means actuated by trip means associated with said cam and follower means, said microswitch being tripped to cause cessation of operation of the linking meachine needles when said work cylinder is pivoted away from the stitching area. 

1. In a linking machine for joining together circular knitted garment sections, the improvement comprising an annular work cylinder having a single, axially extending annular row of points thereon for engaging the loops of a pair of circular knitted garment sections to be joined together by sewing, the said work cylinder supporting at least portions of each of the garment sections to be joined substantially concentrically therein during the linking operation.
 2. In a linking machine including sewing needles for stitching together the loops of circular knitted garment sections to be joined, the improvement comprising an annular work cylinder having points for engaging the loops of the garment sections to be joined; the said work cylinder supporting at least portions of each of the garment sections to be joined substantially concentrically therewithin during the stitching operation, a pivotally mounted support means for mounting said work cylinder on said machine for both rotational motion about its longitudinal axis and pivotal movement about its transverse axis; and actuating means whereby said work cylinder can be pivoted about its transverse axis from a position where the points lie in proximity to the stitching area of the machine to a position where the points are inclined away from the stitching area.
 3. The linking machine of claim 2 wherein said work cylinder support means further comprises a sleeve assembly for coaxially receiving and supporting said work cylinder within said assembly, said sleeve assembly comprising an outer sleeve member and a work cylinder engaging annular inner sleeve member, said inner sleeve member extending coaxially of said outer sleeve member and being pivotally supported for rotary motion about its longitudinal axis with respect to said outer sleeve member, said work cylinder extending axially through said inner sleeve member, said inner sleeve member further including means for engaging said work cylinder whereby the said work cylinder is supported for rotary motion with respect to said outer sleeve member, said outer sleeve member normally being held fixed against rotary motion on said linking machine.
 4. The linking machine of claim 3 wherein the said work cylinder includes a conical tapered outer peripheral area, the tapered periphery converging towards the points of the work cylinder, and said inner sleeve means for engaging said work cylinder includes an inner tapered surface corresponding to the tapered periphery of the work cylinder, the inner sleeve member receiving and engaging the work cylinder through an interference friction fit.
 5. The linking machine of claim 4 wherein said work cylinder includes an annular row of ratchet teeth, and said sleeve assembly further includes a work cylinder driving ring and a pawl connected thereto, said pawl engaging said ratchet teeth for causing intermittent, unidirectional rotary motion of said work cylinder when said pawl is driven in an oscillating manner through said driving ring, and means operating synchronously with the linking machine needles for actuating said driving ring in an oscillating manner.
 6. The linking machine of claim 4 wherein said sleeve assembly further includes a work cylinder quick release means for enabling the work cylinder to be positively driven axially out of engagement with said inner sleeve member.
 7. The linking machine of claim 2 wherein said actuating means for said work cylinder support means comprises a lever arm driven by a cam and follower means, the cam and follower means being driven synchronously with the linking machine needles whereby said lever arm is driven to cause said pivotal movement of said support means away from the needles once per linking cycle after each garment is completely joined.
 8. The linking machine of claim 7 further including a microswitch means actuated by trip means associated with said cam and follower means, said microswitch being tripped to cause cessation of operation of the linking machine needles when said work cylinder is pivoted away from the stitching area. 